DIN Deutsches Institut fr Normung -Instituto alemn de normalizacin.ANSI American National Standards Institute -Instituto Nacional Estadounidense de Estndares.IEC INTERNATIONAL ELECTROTECHNICAL COMMISSION-Comisin Electrotcnica Internacional.

BS British StandardsIEEE Institute of Electrical and Electronics Engineers, internacionalASM American Standard ManualNEMA National Electrical Manufacturers Association, EEUU

*